1. Feature Of The Week

    In this paper, we report what we believe is a novel technique to overcome the depth-of-focus (DOF) limitation in optical coherence tomography (OCT). Using confocal optics on a sample arm, we scanned the illumination beam across the under-filled objective lens pupil plane by steering the beam at the pinhole using a microcylindrical lens. The detected interferometric signals from multiple distinctive apertures were digitally refocused, which is analogous to synthetic aperture radar (SAR). Using numerical simulations and imaging experiments, we verified that this technique can maintain a diffraction-limited transverse resolution along a DOF that is ∼10∼10 times larger than the confocal parameter. The ability to extend the DOF without signal loss and sidelobe artifacts may ultimately overcome the DOF limitation in high-resolution OCT.

    For more information see recent Article. Courtesy Linbo Liu from Courtesy Nanyang Technological University. To share this article click Here.

  2. Recent Articles From Around The Web

    1. Feature Of The Week 06/27/2017: Depth-of-Focus Extension in Optical Coherence Tomography via Multiple Aperture Synthesis

      Feature Of The Week 06/27/2017: Depth-of-Focus Extension in Optical Coherence Tomography via Multiple Aperture Synthesis

      In this paper, we report what we believe is a novel technique to overcome the depth-of-focus (DOF) limitation in optical coherence tomography (OCT). Using confocal optics on a sample arm, we scanned the illumination beam across the under-filled objective lens pupil plane by steering the beam at the pinhole using a microcylindrical lens. The detected interferometric signals from multiple distinctive apertures were digitally refocused, which is analogous to synthetic aperture radar (SAR). Using numerical simulations and imaging experiments, we verified that this technique can maintain a diffraction-limited transverse resolution along a DOF that is ∼10 times larger than the confocal ...

      Read Full Article
    2. University of California at Berkeley Receives NIH Grant for Interferometric Optophysiology of the Human Retina

      University of California at Berkeley Receives NIH Grant for Interferometric Optophysiology of the Human Retina

      University of California at Berkeley Receives a 2017 NIH Grant for $618,742 for Interferometric Optophysiology of the Human Retina. The principal investigato is Austin Roorda. The program began in 2015 and ends in 2020. Below is a summary of the proposed work. Our goal is to develop a new technology for non-invasive optical monitoring of activity of individual retinal neurons and their light-driven inputs at cellular resolution, in the living human retina. If successful, this technology will provide an entirely new and objective approach to understand and monitor treatment of retinal disease, thereby transforming scientific studies of the eye ...

      Read Full Article
    3. Johns Hopkins University Receives NIH Grant for Micro Coherence Imaging Technology for Assessing Obstructive Lung Disease In Vivo

      Johns Hopkins University Receives NIH Grant for Micro Coherence Imaging Technology for Assessing Obstructive Lung Disease In Vivo

      Johns Hopkins University Receives a 2017 NIH Grant for $750,287 for Micro Coherence Imaging Technology for Assessing Obstructive Lung Disease In Vivo. The principal investigator is Robert Brown. The program began in 2014 and ends in 2019. Below is a summary of the proposed work. This Biomedical Research Partnership (BRP) proposal involves a partnership among a biomedical engineering team, a pulmonary physiology team, and a clinical pulmonary medicine team. This research program will incorporate state of the art optical engineering, advanced in vivo physiologic evaluation, and direct application to human obstructive lung diseases (OLD). Optical coherence tomography (OCT) is ...

      Read Full Article
    4. INTRAOPERATIVE IMAGING OF RETAINED PERFLUOROCARBON LIQUID USING SPECTRAL DOMAIN OPTICAL COHERENCE TOMOGRAPHY

      INTRAOPERATIVE IMAGING OF RETAINED PERFLUOROCARBON LIQUID USING SPECTRAL DOMAIN OPTICAL COHERENCE TOMOGRAPHY

      Purpose: To report images of retained perfluorocarbon liquid (PFCL) on the surface of the retina obtained during an intraoperative use of hand-held spectral domain optical coherence tomography. Methods: A 54-year-old man underwent pars plana vitrectomy with injection of PFCL to repair retinal detachment. Postoperatively, visually significant PFCL droplets were found to be retained in the eye. During the surgical removal of PFCL, a hand-held spectral domain optical coherence tomography was used to image the retina with the patient supine. Results: Spectral domain optical coherence tomography images of the retained PFCL illustrated magnification of the areas of the outer retina underlying ...

      Read Full Article
    5. Optical coherence tomography angiography imaging of Purtscher retinopathy

      Optical coherence tomography angiography imaging of Purtscher retinopathy

      Dear Editor: Purtscher retinopathy is an occlusive microvasculopathy associated with trauma and was first described by Purtscher. 1 It usually results from head trauma or chest compression. A similar condition as a result of nontraumatic cause is referred to as “Purtscher-like retinopathy.” The diagnosis is primarily clinical and includes unilateral or bilateral sudden vision loss with fundus features, including cotton wool spots, intraretinal hemorrhage, and pathognomonic Purtscher flecken (retinal whitening with periarteriolar sparing). These features result from the occlusion of precapillary arteriole possibly from fat embolus or leukoaggregates. 2 Fluorescein angiogram may show blocked choroidal fluorescence because of retinal whitening ...

      Read Full Article
    6. Optical Coherence Tomography Angiography According to Severity of Diabetic Retinopathy

      Optical Coherence Tomography Angiography According to Severity of Diabetic Retinopathy

      Purpose To evaluate the extent of macular microvascular changes in diabetic retinopathy according to progression of diabetic retinopathy using optical coherence tomography angiography (OCTA). Methods We retrospectively analyzed 46 diabetic patients and 10 normal patients who underwent OCTA. Diabetic patients were classified as mild, moderate, severe non-proliferative diabetic retinopathy (NPDR), and proliferative diabetic retinopathy (PDR) according to international clinical diabetic retinopathy severity classification fundus findings. OCTA was performed on a 3 × 3 mm region centered on the fovea and parafoveal areas to measure the width of the fovea avascular zone (FAZ) of the superficial and deep capillary plexuses. Results Among ...

      Read Full Article
    7. Automatic detection and recognition of multiple macular lesions in retinal optical coherence tomography images with multi-instance multilabel learning

      Automatic detection and recognition of multiple macular lesions in retinal optical coherence tomography images with multi-instance multilabel learning

      Detection and recognition of macular lesions in optical coherence tomography (OCT) are very important for retinal diseases diagnosis and treatment. As one kind of retinal disease (e.g., diabetic retinopathy) may contain multiple lesions (e.g., edema, exudates, and microaneurysms) and eye patients may suffer from multiple retinal diseases, multiple lesions often coexist within one retinal image. Therefore, one single-lesion-based detector may not support the diagnosis of clinical eye diseases. To address this issue, we propose a multi-instance multilabel-based lesions recognition (MIML-LR) method for the simultaneous detection and recognition of multiple lesions. The proposed MIML-LR method consists of the following ...

      Read Full Article
    8. Optical coherence elastography to assess biomechanics and detect progression of ocular and other tissues degenerative diseases

      Optical coherence elastography to assess biomechanics and detect progression of ocular and other tissues degenerative diseases

      An excitation force (internal or external) and phase-sensitive optical coherence elastography (OCE) system, used in conjunction with a data analyzing algorithm, is capable of measuring and quantifying biomechanical parameters of tissues in situ and in vivo. The method was approbated and demonstrated on an example of the system that combines a pulsed ultrasound system capable of producing an acoustic radiation force on the crystalline lens surface and a phase-sensitive optical coherence tomography (OCT) system for measuring the lens displacement caused by the acoustic radiation force. The method allows noninvasive and nondestructive quantification of tissue mechanical properties. The noninvasive measurement method ...

      Read Full Article
    9. Optical coherence tomography device and control program

      Optical coherence tomography device and control program

      An optical coherence tomography device includes an OCT optical system; a processor. The processor executes: an image generation processing of processing first OCT signals, and generating, based on the first OCT signals, a three-dimensional motion contrast image which is obtained by imaging a moving object in the scanning position; a Doppler shift detection processing of detecting Doppler shift in a scanning position specified on the three-dimensional motion contrast image, the plurality of second OCT signals being detected at timings different from the timings when the plurality of first OCT signals are detected; and a velocity obtaining processing of obtaining an ...

      Read Full Article
      Mentions: Nidek
    10. Multiple window processing schemes for spectroscopic optical coherence tomography (OCT) and fourier domain low coherence interferometry

      Multiple window processing schemes for spectroscopic optical coherence tomography (OCT) and fourier domain low coherence interferometry

      Current apparatuses and methods for analysis of spectroscopic optical coherence tomography (SOCT) signals suffer from an inherent tradeoff between time (depth) and frequency (wavelength) resolution. In one non-limiting embodiment, multiple or dual window (DW) apparatuses and methods for reconstructing time-frequency distributions (TFDs) that applies two windows that independently determine the optical and temporal resolution is provided. For example, optical resolution is provided. For example, optical resolution may relate to scattering information about a sample, and temporal resolution may be related to absorption or depth related information. The effectiveness of the apparatuses and methods is demonstrated in simulations and in processing ...

      Read Full Article
    11. Optical beam scanner

      Optical beam scanner

      A scanning device is presented having a substrate with a first surface and an opposite, parallel second surface. A region of the substrate includes the first surface and the opposite parallel second surface, and is defined via an etching process through a thickness of the substrate, where the region remains attached to the substrate via one or more hinges. A waveguide is patterned over the first surface of the region and guides a beam of radiation along a length of the waveguide. The scanning device includes a facet located on the first surface of the region. The facet is designed ...

      Read Full Article
    12. New SuperK MIR brings supercontinuum into the mid-IR

      New SuperK MIR brings supercontinuum into the mid-IR

      With their ultra-broad spectrum, diffraction-limited beam quality and robust fiber architecture, supercontinuum white light lasers have long been the light source of choice in demanding applications from fluorescence microscopy and bio-imaging to spectroscopy and industrial metrology. Based on NKT Photonics proven supercontinuum platform, the new SuperK MIR now offers the same benefits as the visible and near-infrared sources with an output in the mid-infrared. The SuperK MIR laser delivers more than 450 mW of continuous light from 0.9 to 4.2 μm. The source features a monolithic all-fiber architecture ensuring stability and maintenance-free operation over thousands of hours. The ...

      Read Full Article
      Mentions: NKT Photonics
    13. Intra- and interobserver reproducibility of Bruch's membrane opening minimum rim width measurements with spectral domain optical coherence tomography

      Intra- and interobserver reproducibility of Bruch's membrane opening minimum rim width measurements with spectral domain optical coherence tomography

      Purpose To investigate the reproducibility of Bruch's membrane opening minimum rim width (BMO-MRW) and retinal nerve fibre layer thickness (RNFLT) measurements using spectral domain optical coherence tomography (SD-OCT). Additionally, to investigate the reproducibility of BMO area measurements and fovea to BMO centre (FoBMO) angle. Methods Participants were healthy subjects ( n = 30) and patients with glaucoma ( n = 26). One eye of each participant was scanned to obtain optic nerve head (24 radial B-scans) and peripapillary (one circular B-scan) images by three independent examiners. Additionally, one examiner imaged each participant three times on the same day. Intra- and interobserver reproducibilities were ...

      Read Full Article
    14. Role of Optical Coherence Tomography in Diagnosis and Treatment of Patients with Acute Coronary Syndrome

      Role of Optical Coherence Tomography in Diagnosis and Treatment of Patients with Acute Coronary Syndrome

      Acute coronary syndrome (ACS) is the main cause of death worldwide and the leading cause of disease burden in high-income countries. ACS refers to a constellation of clinical symptoms that are compatible with acute myocardial ischemia. It describes a spectrum of clinical manifestations that result from a common pathophysiological process. The most common cause of ACS are rupture of an atherosclerotic lesion containing a large necrotic core and a thin fibrous cap followed by acute luminal thrombosis. It was thought that a high-resolution imaging modality would be ideal to detect high-risk plaques before their disruption and the formation of an ...

      Read Full Article
    15. Automatic Identification of Intraretinal Cystoid Regions in Optical Coherence Tomography

      Automatic Identification of Intraretinal Cystoid Regions in Optical Coherence Tomography

      Optical Coherence Tomography (OCT) is, nowadays, one of the most referred ophthalmological imaging techniques. OCT imaging offers a window to the eye fundus in a non-invasive way, permitting the inspection of the retinal layers in a cross sectional visualization. For that reason, OCT images are frequently used in the analysis of relevant diseases such as hypertension or diabetes. Among other pathological structures, a correct identification of cystoid regions is a crucial task to achieve an adequate clinical analysis and characterization, as in the case of the analysis of the exudative macular disease. This paper proposes a new methodology for the ...

      Read Full Article
    16. See all articles
  1. Categories

    1. Applications:

      Art, Cardiology, Dentistry, Dermatology, Developmental Biology, Gastroenterology, Gynecology, Microscopy, NDE/NDT, Neurology, Oncology, Ophthalmology, Other Non-Medical, Otolaryngology, Pulmonology, Urology
    2. Business News:

      Acquisition, Clinical Trials, Funding, Other Business News, Partnership, Patents
    3. Technology:

      Broadband Sources, Probes, Tunable Sources
    4. Miscellaneous:

      Jobs & Studentships, Student Theses, Textbooks
  2. Organizations in the News

    1. (2 articles) Tufts University
    2. (2 articles) Harvard University
    3. (2 articles) National Institutes of Health
    4. (2 articles) Massachusetts General Hospital
    5. (2 articles) University of Ulsan
    6. (2 articles) Nanyang Technological University
    7. (1 articles) Johns Hopkins University
    8. (1 articles) University of Wisconsin
    9. (1 articles) Chinese Academy of Sciences
    10. (1 articles) Massachusetts Institute of Technology
  3. People in the News

    1. (2 articles) Jay S. Duker
    2. (2 articles) Linbo Liu
    3. (2 articles) Francesco Bandello
    4. (1 articles) Stephen A. Boppart
    5. (1 articles) Jingbo Hou
    6. (1 articles) Eduardo Margallo Balbás
    7. (1 articles) Giuseppe Querques
    8. (1 articles) Brian J. F. Wong
    9. (1 articles) Adam Wax
    10. (1 articles) Ryan L. Shelton
    11. (1 articles) Benjamin J. Vakoc
    12. (1 articles) Zhongping Chen
    13. (1 articles) Bo Yu
    14. (1 articles) Alexandre S. C. Reis
    15. (1 articles) Haibo Jia
  4. OCT Companies in the News

    1. (1 articles) Nidek
    2. (1 articles) Thorlabs
    3. (1 articles) Topcon Medical Systems
    4. (1 articles) NKT Photonics
    5. (1 articles) MedLumics
    6. (1 articles) Carl Zeiss Meditec
    7. (1 articles) Physical Sciences Incorporated
    8. (1 articles) Compact Imaging, Inc
    9. (1 articles) Gooch & Housego
  5. Picture Gallery

    Compact Imaging Teams with SRI International for  Dynamic Biometrics Development under IARPA Odin Program 16  MHz wavelength-swept and wavelength-stepped laser architectures based on stretched-pulse active mode locking with a single continuously chirped fiber Bragg grating Depth-of-focus extension in optical coherence tomography via multiple aperture synthesis Investigating the influence of organic matter composition on biofilm volumes in reverse osmosis using optical coherence tomography Compact Optical Delay Line for More Efficient OCT Imaging from Gooch & Housego Quantitative Swept-Source Optical Coherence Tomography of Early Enamel Erosion in vivo Pharmaceutical film coating catalogue for spectral-domain optical coherence tomography Introduction to the feature issue on the 25 year anniversary of optical coherence tomography Speckle-modulating optical coherence tomography in living mice and humans Effects of statins on plaque rupture assessed by optical coherence tomography in patients presenting with acute coronary syndromes: insights from the optical coherence tomography (OCT)-FORMIDABLE registry Zeiss Acquisition of Insight Ophthalmic Laser Engines for 19.1M Euros U.S. Engineers James G. Fujimoto and Eric A. Swanson, and German Physicist Robert Huber Win European Inventor Award 2017
  6. Recent Quotes

    1. We showed that you can take effectively any OCT system out there and, with minimal changes, boost its resolution to the point where it can detect anatomical features smaller than the size of a typical cell.
      By Adam de la Zerda
    2. This honor highlights the commitment Avinger has to bring the most advanced technology to market for physicians dedicated to treating PAD and their patients who are affected by this disease...Pantheris radically changes the treatment of vascular disease and the Edison Award represents a win for our entire Lumivascular portfolio.
      By John B. Simpson
    3. While we have been actively advancing our lesion assessment technology for the last two years, we are very pleased to see that the significant Series B investment will give MedLumics the means to complete our best-in-class product, conduct a series of international clinical trials to prove its safety and efficacy, and market it to specialist centers. As the company advances and grows into new areas, we will now expand and develop the team internationally.
      By Eduardo Margallo Balbás
    4. It's the most rapidly adopted ophthalmic technology in history.
      By Joel S. Schuman
    5. Our OCT Angiography congresses is a major force in promoting the transition from FA to OCTA by educating the ophthalmologists .
      By Bruno Lumbroso
    6. The development of OCT in the early 1990s greatly benefited from components and methods used in fiber-optical communications...And still, 25 years later, advances in the optical communications industry continue to greatly benefit OCT.
      By James G. Fujimoto
    7. Research by our group at MIT and our collaborators at Praevium Research and Thorlabs indicated that the coherence length of the VCSEL source was orders of magnitude longer than other swept laser technologies suitable for OCT, which suggested the possibility of long-range OCT imaging.
      By Benjamin M. Potsaid
    8. Our study demonstrates world-record results in cubic meter volume imaging, with at least an order of magnitude larger depth range and volume compared to previous demonstrations of three-dimensional OCT...These results provide a proof-of-principle demonstration for using OCT in this new regime...Long-range OCT is a new range of operation that requires extremely high performance light sources, integrated optical receivers and signal processing.
      By James G. Fujimoto
    9. Research by our group at MIT and our collaborators at Praevium Research and Thorlabs indicated that the coherence length of the VCSEL source was orders of magnitude longer than other swept laser technologies suitable for OCT, which suggested the possibility of long-range OCT imaging.
      By Benjamin M. Potsaid
    10. "The development of OCT in the early 1990s greatly benefited from components and methods used in fiber optical communications,. And still, 25 years later, advances in the optical communications industry continue to greatly benefit OCT.
      By James G. Fujimoto